JPS621232Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a manifold structure for a novel diaphragm electrolytic cell. This is an apparatus for obtaining caustic alkali, halogen gas such as chlorine, and hydrogen by electrolyzing an aqueous solution of an alkali metal halide, especially sodium chloride and potassium chloride.

Conventionally, methods for electrolyzing alkali metal halides are well known, and a diaphragm type electrolytic cell is generally used. Filter press type and pool type electrolytic cells are used. Pool type electrolytic cells are, for example, electrolytic cells developed by Diamond Shamlok Co., Ltd., Hooker Chemical Co., Ltd., Nippon Soda Co., Ltd., etc. Either the liquid or the anolyte exists in a common pool, and the other is an anode chamber (or cathode chamber) in which at least the current-carrying surface is divided by a diaphragm.
Since the polar chamber is configured to exist within the pool, the polar chamber generally has a structure in which both sides thereof are in contact with the liquid in the pool, so a monopolar type is advantageous to use this effectively. The present invention proposes a new structure for the manifold used in the above-mentioned pool type electrolytic cell.The manifold in the present invention extends almost the entire length of the diaphragm type electrolytic cell and is located at the top of the electrolytic cell, and is located at the top of the electrolytic cell. It has a structure in which a discharge pipe for extracting liquid and gas from each chamber (or cathode chamber) in a multiphase flow and a liquid supply pipe for supplying liquid to each anode chamber (or cathode chamber) are connected respectively. be.

In the present invention, the liquid in the manifold may be either an anolyte or a catholyte; however, in the present invention, an embodiment using an anolyte is shown below.

Conventionally, as the above-mentioned manifold, one having the structure shown in FIG. 1 has been used. That is, the anolyte containing chlorine gas generated by electrolysis is extracted into the manifold through the discharge pipe 2, and the anolyte at a constant concentration is supplied to each anode chamber through the supply pipe 3. Chlorine gas is discharged to the outside of the system through the gas vent port 4. At this time, the concentration of the anolyte decreases due to electrolysis, so a replenishment liquid is required to maintain the constant concentration and supply the anolyte, and this liquid is supplied from the solution replenishment port 5. Both liquids are mixed in the manifold, balanced to a constant concentration, and a portion is extracted from the system through the outlet 6.

However, in conventional manifolds, high-concentration replenishment liquid supplied from the outside is supplied from one point of the manifold and taken out from one end of the manifold, and since the manifold has a one-chamber structure, it is necessary to supply the replenishment liquid and electrolysis. Mixing with the circulating fluid becomes non-uniform, and the concentration of the supply solution supplied from the manifold to each anode chamber is high near the solution supply port 5 and decreases as it moves away from the supply port. For this reason, the concentration of the anolyte supplied from each liquid supply pipe 3 varies, and when such aqueous solution is used, the electrolytic conditions become non-uniform, which is not preferable. Furthermore, in conventional manifolds, it has been difficult to control the concentration in each liquid supply pipe to a constant level.

The present invention presents a new manifold structure to solve the above problem, and its gist is that the manifold is located at the top of the electrolytic cell over almost the entire length of the diaphragm electrolytic cell.
A manifold in which a discharge pipe for extracting liquid and gas from each anode chamber (or cathode chamber) in a multiphase flow and a liquid supply pipe for supplying liquid to each anode chamber (or cathode chamber) are respectively connected. The manifold is divided into two in the longitudinal direction, one of which constitutes a solution supply chamber to which the liquid supply pipe is connected, and the other constitutes a solution circulation chamber to which the discharge pipe is connected,
The solution supply chamber and the solution circulation chamber are connected near one end of the manifold, and have a solution supply port near the communication portion and a solution takeout port near the other end. This is the structure of the manifold of a diaphragm type electrolytic cell.

The manifold of the present invention has a structure that has a solution supply chamber and a solution circulation chamber that are divided into two in the longitudinal direction, so that the flow of the solution can be kept constant. Therefore, the dilute circulating fluid and the concentrated replenishing fluid can be uniformly mixed in the manifold, making it easy to constantly supply a constant concentration of fluid to each anode chamber.

In addition, in the present invention, the mode in which the manifold is divided into two chambers, the solution supply chamber and the solution circulation chamber, allows the solution to be separated into the two chambers without completely partitioning the gas phase, such as by partitioning with a partition plate. It's good to have.

In the present invention, known materials and shapes can be used for the manifold and the partition plate for dividing the manifold into two parts in the longitudinal direction. For example, the material may be metal or plastic that has solution resistance and gas properties, the shape of the manifold is generally cylindrical or mesh, and the partition plate is made of the above material and has a diameter of 1 to 5 mm.
Any structure that allows the two chambers to be separated by a thick plate may be used.

The present invention will be explained below based on the drawings.

Fig. 2 is a perspective view showing the manifold of the present invention, Fig. 3 is a schematic diagram showing how one anode chamber and the manifold are connected, and Fig. 4 is a front view of the manifold part of Fig. 3. It is something.

FIG. 2 is a perspective view of the manifold of the present invention. The manifold 7 extends almost the entire length of the diaphragm electrolytic cell 13 and is located above the electrolytic cell, and is a discharge pipe for extracting liquid and gas from each anode chamber 1 in a multiphase flow. 2 and a liquid supply pipe 3 that supplies liquid to each anode chamber 1 are connected, and the manifold is divided into two in the longitudinal direction by a partition plate 8 into a solution circulation chamber 9 and a solution supply chamber 10. 10 and the solution circulation chamber 9 are connected to each other near one end 11 of the manifold, and have a solution supply port 5 near this part and a solution outlet 6 near the other end. Further, the gas in the anolyte is led out of the system through the gas vent port 4.

The feature of the manifold of the present invention is that the solution circulation chamber 9 is divided into the manifold by a known method such as partitioning with a partition plate.
and a solution supply chamber 10.

For this purpose, the anolyte extracted from each anode chamber 1 through the discharge pipe 2 is circulated to the anode chamber 1 in the direction of the arrow in FIG. 3 (schematic diagram showing the state of connection between one anode chamber and a manifold). Part of it is discharged from the system through the outlet. The state in which the replenisher was further added is shown below. That is, although FIG. 4 shows a plan view of the manifold of the present invention (arrows indicate the flow state of the solution), the present invention is divided into a solution circulation chamber 9 and a solution supply chamber 10 by a partition plate 8, and both chambers are separated from each other by a partition plate 8. are connected near one end 11 of the manifold, and have a solution supply port 5 there, so that the anolyte extracted from the discharge port 2 flows in the direction of the arrow and flows near one end 1
Since the concentrated replenishment liquid is supplied at step 1, the circulating fluid and the replenishment liquid are mixed uniformly and thickly at this portion (mixing section) 11. Therefore, when the liquid is supplied to each anode chamber 1, a constant concentration can be maintained at all times.

At this time, if the solution supply chamber 10 has a structure in which a solution outlet 6 is provided through a weir 12 near the other end, the height of the liquid level in the solution supply chamber 10 is determined by the height of the weir. This is preferable because the flow rate and concentration of the liquid supplied from the solution supply chamber 10 to the anode chamber 1 can be easily controlled. The relationship between the state of the liquid flowing in the manifold and the weir will be explained with reference to FIGS. 5A and 5B. Figure 5 A shows the manifold A- in Figure 4.
It is a view cut along the plane A' and viewed in the direction of the arrow. The manifold is divided into a solution circulation chamber 9 and a solution supply chamber by a central partition plate 8. The liquid level in the solution supply chamber is kept almost constant by a weir 12, and the solution in the solution supply chamber is A portion of the solution overflows from the weir 12 and is discharged from the solution outlet 6. FIG. 5B is a view of the manifold shown in FIG. 4 cut along line B-B' and viewed in the direction of the arrow. In this figure, with the central partition plate 8 as a boundary, there is a difference between the liquid level in the solution circulation chamber 9 shown on the left side and the liquid level in the solution supply chamber 10 also shown on the right side. That is,
The solution circulation chamber side is bulky because it contains some gas due to the multiphase flow of liquid and gas discharged from the anode chamber, but in the solution supply chamber side, the gas in the liquid has already been removed. Moreover, some of the solution is being supplied to the anode chamber, so the liquid level is low. However, it usually does not go below cough height. In other words, the height of the solution in the solution supply chamber is controlled by the height of the weir.

The present invention is particularly characterized in that by dividing the inside of the manifold into two, a flow path for the extracted liquid and the supplied liquid is ensured, and at one end of the flow path, there is a solution replenishment port for adjusting the concentration of the extracted liquid. As for other structures, known structures can be used without restriction.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the structure of a conventional manifold for diaphragm electrolysis, and FIG. 2 is a perspective view of the manifold of the present invention. FIG. 3 is a diagram showing the flow of solution between the manifold of the present invention and the anode chamber (or cathode chamber), FIG. 4 is a cross-sectional view of the manifold of the present invention, and FIG. B is a cross-sectional view of the manifold shown in FIG. 4 taken along the plane A-A' and the plane B-B'. In the figure, 1 is an anode chamber, 2 is a discharge pipe, 3 is a liquid supply pipe, 4 is a gas vent, 5 is a solution supply port, 6 is a discharge port, 7 is a manifold, 8 is a partition plate, 9 is a solution circulation chamber, 10 is a solution supply chamber, 11 is a solution mixing section, 1
2 is a weir, and 13 is an electrolytic cell.

Claims (1)

[Scope of utility model registration request] Exhaust pipes and each anode chamber (or cathode chamber) that extend over almost the entire length of the diaphragm electrolyzer and are located at the top of the electrolyzer, and are used to extract liquid and gas from each anode chamber (or cathode chamber) in a multiphase flow. a manifold to which liquid supply pipes for supplying liquid to each are connected, the manifold being divided into two in the longitudinal direction, one of which constitutes a solution supply chamber to which the liquid supply pipes are connected;
The other side constitutes a solution circulation chamber to which the discharge pipe is connected, and the solution supply chamber and the solution circulation chamber are connected near one end of the manifold, and a solution supply port is provided near the communication section. 1. A manifold for a diaphragm electrolytic cell, characterized in that the manifold has a solution outlet near the other end.